Vacuum cleaner



Jan. 12, 19 3- F.',C. DOUGHMAN VACUUM CLEANER Filed Jul 19, 1940' s atente Jan. 1, N43

vacuum crap Application July 19, 1940, Serial No. 346,242

6 Claims.

My invention relates to vacuum cleaners and.

more particularly to the motor-fan unit support within the vacuum cleaner casing,

In vacuum cleaners of the type having a unit which is pulled around on the floor by a flexible hose, a motor-fan unit is mounted in this unit. The motor is usually a universal type motor which operates at a relatively high speed when connected either to alternating or direct current. A motor of this type has a commutator with a number of segments engaged by two carbon brushes. High frequency electrical pulsations are created as the commutator segments pass successively under the carbon brushes. The slots in the armature also produce high frequency electrical pulsations. These electrical pulsations are con- Referring to the drawing, i0 indicates a vacuum cleaner casing housing a motor ll, driving a multi-stage fan i2 which produces a flow of air in the casing in from left to right, as shown in Fig. 1. At the left end in casing II), a dust separating member or dust bag I3 is located.

Motor H is provided with an end shield it formed of a phenolic condensation product such as Bakelitef Formed integrally with end shield 14 are two brush holders IE to which are secured brush holder caps It. End shield I6 is secured verted into mechanical vibrations in the motor primarily as torque pulsations. When the motor the alternating impulses are also converted into mechanical vibrations. The variations in the load on the motor as the vacuum cleaner is operated, which produce variations in the speed of operation of the motor, are also converted into mechanical vibrations. Any mechanical unbalance in the armature will produce vibrations. The multi-stage fan which is connected to the motor with its plurality of blades produces mechanical vibrations. All of these mechanical vibrations produce noise, if not absorbed, which is magnifled if transmitted to the vacuum cleaner casing. A flexible support for the motor-fan unit has been used heretofore to reduce the noise produced and transmitted to the vacuum cleaner casing.

An object of my invention is to provide an improved motor-fan unit support.

A further object of my invention is to eliminate the transmission of vibrations and noise from the motor-fan unit to the vacuum cleaner casing- What I consider to be novel and my invention may be better understood by reference to the following specification and accompanying drawing, in which:

Fig. l is a side view of a vacuum cleaner unit broken away in part to show the motor-fan unit and dust bag within it;

Fig 2 is a. cross-sectional view taken along the line 2-2 of Fig. 1;

Fig. 3 is an enlarged detail sectional view taken along the line 3-3 of Fig. 2;

Fig. 4 is an enlarged detail sectional view taken along the lines 4-4 of Fig. 3: and

Fig. 5 is an enlarged detail view taken along the line 5-5 of Fig. 4.

to a steel motor housing shell H by means of bolts l8. Three brackets 19 are secured to shell H at radially spaced points around the periphery of the shell. Three resilient supporting members 29 consisting of a fiat metal strap 2!, a metal angle member 22, and a block 23 of rubber or other resilient material are provided. Block 23 is secured to strap 2| and angle member 22 by means of vulcanization. Strap 2! is secured to bracket 89 by means of two screws Ed in threaded engagement with strap 2|. Angle members 22 are secured, to an annular ring 25 as by means of. rivets 26.

Fan l2 includes two rotating fan members 27 and 28 secured to the end of shaft extension 29 of motor ll. Between the fan members 21 and 28 is located a guide member 30, which serves to guide air discharged from-fan 27 to the inlet of fan 28. Guide member 30 is secured to a housing 3| surrounding fan 28. A second fan housing 32 surrounds fan 2? and is secured to fan housing 3!. Fan housing 3! is closed by an end wall 33 secured to shell ll.

A bulkhead 3% is secured within vacuum cleaner casing iii and is provided with an opening to receive motor H and fan i2. Annular ring 25 is secured to bulkhead 36 by means of bolts 35 to mount the motor H and fan 12 within casing Ill. The space between fan housings 3| and 32 and easing ill is closed by a flexible sealing ring 36. Sealing r g 36 has a radially extending flange 31 positioned between bulkhead 3t and annular ring 25. An enlarged end 38 of sealing ring 35 remote from flange 3T abuts end wall 33.

When motor H and fan l2 are operated the electrical impulses tending to produce mechanical vibrations and noise appear as radial or rotary vibrations. The relatively small widths of the blocks 23 provide extreme flexibility to rotary vibrations with blocks 23, under shear, readily absorbing any such vibrations. Variations in the load on the motor tend primarily to produce axial vibrations which are of lower frequency than the rotary vibrations mentioned above. The axial vibrations are equally well absorbed by the blocks 23, which are relatively short in length, so provide.

considerable flexibility when the blocks 23 are under shear in an axial direction.

The operation of motor ii and fan I! produces a flow of air from left to right in casing ID, as shown in Fig. 1. This operation of the motor-fan unit produces a force on the motor ii and fan i! moving it toward the left or in a direction opposite to the direction of air movement. The flexibility of the supporting members 20 permits conmembers together, an annular metal ring securedto the radial extending portions offsaid. angle siderable movement of the motor-fan unit in this direction. When the motor-fan unit is not op crating, the flexible sealing ring 36 has a con:-

siderable portion of its free end in engagement with wall 33 as shown in Fig. 3. When the motor-fan unit is operated movement of the motor H and fan 12 to the leitreduces the portion of sealing ring 36 in-engagement-withwall 33, but the end 38 and a small adjacent portion of ring it retains the seal to prevent air flow between casing in and the fan housings 3| and 32.

When motor ll moves axially, bracket I9 and.

strap 2| move with respect to angle member 22. An upturned shoulder 89 provided on the end of angle member '22 serves as a stop to prevent undue movement of motor H toward the left, as shown in Fig. 3, by engagement with bracket l9.

Axial movement oi motor H in the opposite di-' ment oi them.

What I claim is: a

1. A vacuum cleaner including a casing, a motor located within said casing, a plurality oi brackets secured to said motor, straps secured to said brackets, angle members secured to said casing and having an axiallyextending portion overlying said straps, and blocks of rubber resiliently connecting said straps and said angle members togetherjsaid angle members having stops adapted to engage said brackets to limit axial movement of said motor and serving to support said motor in said casing.

2. A vacuum cleaner including a casing, a bulkhead located within said casing having an opening, a motor located in said casing extending through the opening in said bulkhead, a plurality of brackets secured to said motor, straps connected to said brackets, angle members having axially extending. portions overlying said 'straps and radially extending portions, blocks oi rubber resiliently securing said straps and said angle members, and means'to secure said annular ring to said bulkhead.

- 3. Apparatus adapted to be used in a vacuum cleaner comprising housing means including a tank, means ior producing air flow through the tank, resilient means for supporting theair flow means within the tank, and resilient sealing means for preventing circulation oi air from one .end of the airflow means to the other without the air going outside the tank, saidsealing means comprising an annular member sealingly attached to one of the two first mentioned means and biased into sealing engagement with a radial face of the other or said two first mentioned means and adapted to remain in such sealing engagement despite axial movement oi the air flow means.

4. A vacuum cleaner tank, means for producing air flow through the tank, resilient means for supporting the air flow means within the tank, and resilient sealing means for preventing circulation of air from one end of the air flow means to the other without the air going outside the tank, said sealing means comprising a resilient member sealingly attached to the tank -and in sealing engagement with the air flow means, the portion of said member attached to the tank forming a part of the resilient supporting means.

5. A vacuum cleaner tank of generally tubular shape, means for producing air flow through the tank, resilient means for supporting the air flow means within the tank, sai'd resilient means comprising a pluralityof rubber sandwiches, the

planes of said sandwiches being substantially parallel to the axis of the tank, and stop means formed on one oi the outer layers of one'oi' said sandwiches adapted to engage means comprising the otherouter layer of the same sandwich upon axial displacement of said air flow means to prevent further axial displacement.

6. A vacuum cleaner tank of generally tubular shape adaptedrwhen in use to be placed with its axis in a substantially horizontal position, means for producing air flow through the tank, resilient means for supporting the air new means within I the tank, said resilient means comprising a. pinrality oi rubber sandwiches, the planes ofsaid sandwiches being substantially perpendicular to radial lines through their centers perpendicular to the axis of the tank, and stop means formed on one of the outer layers of one of said sandwiches adapted to engage means comprising the outer layer of the same sandwich upon downward displacement of said air flow means to further downward displacement.

mm c. DOUGHMAN; I

prevent 

